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Biomedical subjects

N Kawaguchi

Publications and source records attributed to N Kawaguchi.

At least 145 records · Page 8Linked to original sources
PubMed1979

Susceptibility of kappa-casein components to various proteases.

In order to clarify the function of the carbohydrate moiety of bovine kappa-casein, kappa-casein components having different carbohydrate contents were prepared by DEAE-cellulose chromatography. Five adsorbed fractions so obtained had an identical peptide chain and contained carbohydrate moieties of increasing size in the order of components P-2, P-3, P-4, P-5 and P-6. The subsceptibility of kappa-casein components, having different carbohydrate contents, to various proteases was examined. kappa-Casein components were subjected to calf rennin [chymosin; EC 3.4.23.4], bovine trypsin [EC 3.4.21.4], alpha-chymotrypsin [EC 3.4.21.1], pronase [EC 3.4.24.4] and human plasmin [EC 3.4.21.7]. The component containing a larger carbohydrate moiety was less susceptible to hydrolysis than the component containing a smaller carbohydrate moiety. Rennin, trypsin, alpha-chymotrypsin and pronase hydrolyzed each component with a different reaction rate. On the contrary, human plasmin hydrolyzed component P-2, but did not hydrolyze component P-5. These results indicate that the carbohydrate moiety of kappa-casein components to various proteases.

Carbohydrate Metabolism↗
PubMed1979

Minor components of reduced bovine kappa-casein.

Bovine kappa-casein reduced with 2-mercaptoethanol was fractionated on a DEAE-cellulose column to one nonadsorbed, five major adsorbed and two minor adsorbed fractions. The properties of the nonadsorbed and five major adsorbed fractions were reported in our previous paper (4). In this paper, the characteristics of two minor adsorbed fractions (P-X and P-Y) were reported. Gel electrophoretic patterns of these fractions were similar to kappa-casein. These fractions had the same amino acid composition and the same phosphorus content as the major components. P-X contained one residue each of N-acetylneuraminic acid, galactose and galactosamine, and P-Y two residues each. Furthermore, these fractions showed the stabilizing ability for alpha s1-casein in the presence of calcium ion. These results indicate that P-X and P-Y are minor components of reduced bovine kappa-casein.

Amino Acids↗